8 TROUBLESHOOTING GUIDE
DANGER: HIGH VOLTAGES
1.
DO NOT RE-ADJUST PRESET CONTROL on the H.V.Inverter (U).
It is very dangerous to repair or adjust without proper test equipment
because this circuit generates very large current and high voltage. Operating a misaligned inverter circuit is dangerous.
2. Ensure proper grounding before troubleshooting.
3. Be careful of the high voltage circuitry, taking necessary precautions when troubleshooting.
4. Discharge high voltage remaining in the H.V.Inverter (U).
5. When checking the continuity of the switches or the H.V.Inverter, disconnect one lead wire from these parts and then check continuity with the
AC plug removed. Doing otherwise may result in a false reading or damage to your meter. When disconnecting a plastic connector from a
terminal, you must hold the plastic connector instead of the lead wire and then disconnect it, otherwise lead wire may be damaged or the
connector cannot be removed.
6. Do not touch any parts of the circuitry on the digital programmer circuit, since static electric discharge may damage this control panel. Always
touch ground while working on this panel to discharge any static charge in your body.
7. 120V AC is present on the digital programmer circuit (Terminals of power relay’s and primary circuit of Digital Programmer Circuit). When
troubleshooting, be cautious of possible electrical shock hazard.
Before troubleshooting, operate the microwave oven following the correct operating procedures in the instruction manual in order
to find the exact cause of any trouble, since operator error may be mistaken for the oven’s malfunction.
8.1. (Troubleshooting) Oven stops operation during cooking
SYMPTOM
CAUSE
CORRECTIONS
1.
Oven
stops
in
3
seconds
after
pressing [Start] pad
No 120V AC is supplied to H.V.Inverter (U) CN702
terminals
1. Latch Switch
2. Power relay RY1
3. Loose lead wire connector CN701, CN702
4. H.V. Inverter (U)
Oven
stops
in
37
seconds
after
pressing [Start] pad
H.V.Inverter (U) operates by the control signals
from DPC but magnetron is not oscillating
1. Magnetron
2. Loose lead wire connector CN703
3. H.V. Inverter (U)
Oven
stops
in
10
seconds
after
pressing [Start] pad
(Auto sensor cooking)
Steam sensor circuit is not functioning
1. Steam sensor
2. DPC
3. Open or loose wiring of sensor terminal
from connector CN2 on DPC
2.
No display and no operation at all.
Fuse is blown.
Most probably loose connection of connectors, or
door latch mechanism is not adjusted properly
1. Allign door, Door Latch Switches
2. Loose wiring connectors
19
NN-SD698S / NN-ST678S / NN-ST658W
Содержание NN-SD698S
Страница 2: ...2 NN SD698S NN ST678S NN ST658W ...
Страница 3: ...3 NN SD698S NN ST678S NN ST658W ...
Страница 5: ...1 SCHEMATIC DIAGRAM 5 NN SD698S NN ST678S NN ST658W ...
Страница 23: ...8 6 How to check the semiconductors using an OHM meter 23 NN SD698S NN ST678S NN ST658W ...
Страница 24: ...9 EXPLODED VIEW AND PARTS LIST 9 1 EXPLODED VIEW 24 NN SD698S NN ST678S NN ST658W ...
Страница 33: ...10 DIGITAL PROGRAMMER CIRCUIT 10 1 NN SD698S 33 NN SD698S NN ST678S NN ST658W ...
Страница 34: ...34 NN SD698S NN ST678S NN ST658W ...
Страница 35: ...10 2 NN ST678S 35 NN SD698S NN ST678S NN ST658W ...
Страница 36: ...36 NN SD698S NN ST678S NN ST658W ...
Страница 37: ...10 3 NN ST658W 37 NN SD698S NN ST678S NN ST658W ...
Страница 38: ...38 NN SD698S NN ST678S NN ST658W ...
